Daigassou! Band Brothers was one of Nintendo DS's early releases in Japan, an internally developed rhythm game that let players perform on different instruments by following on-screen notes, with a strong social component thanks to the ability to form bands of multiple wirelessly connected players, each with their own instrument.
It never left Japan under this name, but it laid the groundwork for the saga that would become known in the West as Jam with the Band; it's a key piece for understanding how Nintendo envisioned DS's social connectivity from the console's very first day.
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